The applicant, Pamela P. Jones, Ph.D., is a physiologist currently supported by an Individual National Research Service Award from NIA. Dr. Jones has demonstrated a consistent focus and record of research productivity in the area of autonomic nervous system (ANS) regulation of energy metabolism and cardiovascular function in humans. Her career goal is to develop an independent, extramurally-funded research program in this area as it pertains to gerontology and geriatric medicine. The KO1 Mentored Research Scientist Development Award would provide the opportunity to extend her current research skills to achieve this goal. Career Development/Training Plan. The training plan consists of 2 primary elements: 1) the acquisition of an impressive number of new research skills; and 2) structured activities including formal course- work in research ethics, biostatistics, and gerontology/geriatric medicine; participation in journal clubs and seminar series; regular mentoring interactions; and attendance/presentation at scientific meetings. A team of established senior investigators with expertise in all aspects of the proposed training plan has been formed to mentor Dr. Jones. Research Plan. The central theme of the research project is to determine the role of the ANS in the attenuated increase in energy expenditure (reduced thermic effect of food-TEF) and the fall in arterial blood pressure (postprandial hypotension) associated with feeding in older healthy sedentary humans. A secondary theme will be to determine if older adults who exercise regularly demonstrate a greater TEF and an absence of postprandial hypotension compared to sedentary older adults. Five specific aims have been developed to address these issues. The general hypothesis is that the lower TEF and postprandial hypotension observed in older sedentary adults will be related to an attenuated increase in sympathetic nervous system (SNS) activity. In contrast, physically active older adults will, in comparison, demonstrate a greater TEF, no postprandial hypotension, and an augmented SNS response. The expected results should provide new and clinically useful information concerning the influences of sedentary aging and habitual physical activity on an important component of body weight regulation (TEF) as well as cardiovascular disease risk (postprandial hypotension). Environment. The environment for Dr. Jones training is excellent. The sponsor, Douglas R. Seals, Ph.D., is an established investigator and mentor in aging research, and has a well-funded laboratory. He and the host department will provide Dr. Jones all of the necessary resources to successfully complete her training.